This is pretty much exactly what I’m looking for, but according to the reviews it automatically shuts off after an hour which sounds very annoying.

https://www.amazon.com/Life-Gear-Flashlight-Whistle-Lanyard/dp/B004D33ONK/ref=pd_lpo_vtph_469_bs_t_1?_encoding=UTF8&psc=1&refRID=M5BCJ2EW8JV8PERJG39H